CVE-2026-87119

Description (CNA)

Authentication Bypass by Capture-replay in ZenHive mpp allows an attacker holding a captured subscription activation credential to charge the payer repeatedly. The payer signs a Tempo KeyAuthorization over the chain id, key type, key id, expiry, limits and scopes only, with nothing tying it to the challenge that prompted it. MPP.Methods.Tempo.KeyAuthorization.verify/3 in lib/mpp/methods/tempo/key_authorization.ex pins each of those signed fields against the subscription request, and the access key it pins is a static per-endpoint server key, so one signed authorization verifies against every challenge the server issues for the same subscription terms. MPP.Methods.Tempo.Subscription.activate/4 deduplicates activations by challenge id, so presenting the captured credential under a fresh challenge produces a different dedup key, claim_activation succeeds, and the subscription transaction is built and broadcast again. Each replay charges the payer's wallet a new first-period settlement and re-authorizes the server key, bounded only by the subscription expiry and the chain's own semantics for re-installing an existing key. This issue affects mpp: from 0.14.0 before 0.16.2.

Affected (CNA)

CWE

CWE-294

References

• https://github.com/ZenHive/mpp/security/advisories/GHSA-p9fv-9w58-95x2
• https://cna.erlef.org/cves/CVE-2026-87119.html
• https://osv.dev/vulnerability/EEF-CVE-2026-87119
• https://github.com/ZenHive/mpp/commit/db464dfa9a86ccda58f0827101f6da6bd8aafa78
• https://github.com/ZenHive/mpp/commit/4b6eaec02af0e8485cfb4ff68f467d075ed5dd6f

ADP enrichment